AMSTERDAM, Jan 29 (Reuters) – A young Dutch-speaking man wielding a pistol forced his way into the studios of the national broadcaster NOS on Thursday demanding to be allowed to go on air, but was quickly arrested, television footage showed.

The man, who appeared to be in his 20s, wore a black suit and tie and entered the studio after threatening a guard with a pistol, witnesses said.

Footage aired on Dutch TV showed the man pacing in the studio with the black pistol behind his back.

“This is taking too long,” he said. Then police stormed into the studio yelling “Drop it! Drop it! And get on your knees!”. He dropped the gun, saying “I dropped it. It’s dropped”, and the police put handcuffs on him and took him away.

An NOS radio reporter said no one had been hurt. NOS television stopped broadcasting because the studios had been evacuated.

The man’s motive was unclear; the NOS footage showed him saying: “The things that are going to be said (pause) those are very large world affairs. We were hired by the security service.”

Police special forces were sweeping the building for explosives and to make sure the man had acted alone, police spokesman Christine Scholts said.

“We are currently investigating who this man is and what he wants,” she said. The police were looking into claims that he had accomplices around the country with explosives.

“He took the security guard hostage and said he wanted air time. If they didn’t give it to him, he said there would be bombs in different places in the Netherlands that would explode if he didn’t get time on TV,” Scholts said.

The threats were reportedly also contained in a letter that the man took to the studio, a purported copy of which was aired by the RTL news channel.

“Realise that I am not on my own,” it said. “Furthermore, eight high explosives have been planted that contain radioactive material. If you don’t take me to studio 8 to make my broadcast, we will be forced to step into action.”

Reuters could not verify whether the letter shown by RTL was genuine.

Security has been tightened across Europe since jihadist attacks on the offices of the satirical weekly Charlie Hebdo and a kosher supermarket in Paris this month, as well as the killing of two gunmen in Belgium during raids on an Islamist group that authorities said were planning to attack police.

NOS television said the gunman appeared to be a student who had recently lost both parents. It also said he did not figure on security services’ lists of suspected Islamist militants.

NOS produces the most widely-watched television newscast in the Netherlands and is based in the main national broadcast park in Hilversum.

Security has been tight there since populist politician Pim Fortuyn was shot outside a studio in 2002.

As the gunman entered the studios on Thursday, NOS’s main news channel displayed a message that read: “In connection with circumstances, no broadcast is available at this time.”